Measured by its ability to induce fluorescence in Lin28 reporter cells (293 cells transfected with fluorescent protein genes under Lin28 control). Optimum activity was achieved at 20 μg/ml after incubation for 72 hr.

Species Reactivity

Human

Synonyms

CSDD1, LIN28A, ZCCHC1, Zinc finger CCHC doamin-containing protein 1

Description

Lin28 is a RNA-binding protein that belongs to a diverse family of structurally-related transcription factors. Lin28 is found abundantly in embryonic stem cells (ESCs), and to a lesser extent in placenta and testis. Lin28 has been shown to block let-7 microRNA processing and maturation, a necessary step in the differentiation of stem cells and certain cancer cell lines. Together with Sox2, Oct4, and Nanog, Lin28 can induce the reprogramming of primary human fibroblasts to a pluripotent state. Lin28 and other regulatory proteins can be introduced into cells by DNA transfection, viral infection, or microinjection. Protein transduction using TAT fusion proteins represents an alternative methodology for introducing proteins into primary as well as transformed cells. Recombinant human Lin28-TAT is a 24.4 kDa protein containing 222 amino acid residues, including 13- residue C-terminal TAT peptide.